【摘要】 用有效质量理论研究了[001]和[111]方向生长的In_xGa_1-xAs/GaAs应变超晶格的电子结构.具体计算了价带能级的色散曲线和光吸收曲线.沿[001]方向生长的光吸收曲线与实验进行了比较.内应变使重轻空穴能级发生上升和下降.由于压电效应,[111]方向生长的超晶格应变层内存在很强的内电场（1.5×10⁵V/cm）,而对[001]方向生长的应变超晶格不产生内电场.更多还原

【Abstract】 The electronic structures of [001]- and [111]-oriented strained-layer superlattices are stu-died by using effective mass theory. The dispersion curves of valance energy levels and optical.absorption curves are obtained. The optical absorption curves for the [001] case are comparedwith experimental results. Under the internal strains, the energy levels of the heavy and lightholes shift up and down. The internal strains in [111]- oriented strained-layer superlatticesgenerate polarization field (1.5×10~5 V/cm) by the piezoelectric effect. Such strain-induced fie-lds do not occur for the [001] case.更多还原